Add yaml-lint-disable comment to suppress diagnostics per-line

Add support for suppressing linter diagnostics on a per-line basis using a yaml-lint-disable comment placed on the line immediately before the one producing the diagnostic.

The comment supports three forms: suppress all diagnostics, suppress by message substring, or suppress by multiple comma-separated substrings (case-insensitive). Implemented via LSP client middleware that intercepts diagnostics from the yaml-language-server and filters out suppressed ones before they reach VS Code.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: 2 people

README.md

@@ -69,6 +69,33 @@ The following settings are supported:
 - `yaml.keyOrdering` : Enforces alphabetical ordering of keys in mappings when set to `true`. Default is `false`
 - `yaml.extension.recommendations` : Enable extension recommendations for YAML files. Default is `true`
 
+## Suppressing diagnostics
+
+You can suppress specific validation warnings on a per-line basis by adding a `# yaml-lint-disable` comment on the line immediately before the one producing the diagnostic.
+
+### Suppress all diagnostics on a line
+
+```yaml
+# yaml-lint-disable
+version: 123
+```
+
+### Suppress only specific diagnostics
+
+Provide one or more message substrings (comma-separated, case-insensitive). Only diagnostics whose message contains a matching substring will be suppressed; the rest are kept.
+
+```yaml
+# yaml-lint-disable Incorrect type
+version: 123
+```
+
+```yaml
+# yaml-lint-disable Incorrect type, not accepted
+version: 123
+```
+
+The substrings are matched against the diagnostic messages shown in the VS Code **Problems** panel.
+
 ## Adding custom tags
 
 To use the custom tags in your YAML file, you need to first specify the custom tags in the setting of your code editor. For example, you can have the following custom tags:

src/diagnostic-filter.ts

@@ -0,0 +1,96 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Red Hat, Inc. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+/**
+ * Pattern that matches a `# yaml-lint-disable` comment.
+ *
+ * Usage in YAML files:
+ *   # yaml-lint-disable                          ← suppress ALL diagnostics on the next line
+ *   # yaml-lint-disable Incorrect type            ← suppress diagnostics whose message contains "Incorrect type"
+ *   # yaml-lint-disable Incorrect type, not accepted  ← suppress diagnostics matching any of the substrings
+ *
+ * Capture group 1 (optional) contains the comma-separated list of message
+ * substrings to match against. If absent, all diagnostics are suppressed.
+ */
+export const YAML_LINT_DISABLE_PATTERN = /^\s*#\s*yaml-lint-disable\b(.*)$/;
+
+/**
+ * A callback that returns the text content of a given zero-based line number,
+ * or `undefined` if the line does not exist.
+ */
+export type GetLineText = (line: number) => string | undefined;
+
+/**
+ * Parse the text after `yaml-lint-disable` into an array of trimmed,
+ * lower-cased message substrings.  Returns an empty array when no
+ * specifiers are provided (meaning "suppress all").
+ */
+export function parseDisableSpecifiers(raw: string): string[] {
+  const trimmed = raw.trim();
+  if (!trimmed) {
+    return [];
+  }
+  return trimmed
+    .split(',')
+    .map((s) => s.trim().toLowerCase())
+    .filter((s) => s.length > 0);
+}
+
+/**
+ * Determine whether a diagnostic should be suppressed based on the
+ * specifiers from a `# yaml-lint-disable` comment.
+ *
+ * @param specifiers - Parsed specifiers (empty means suppress all).
+ * @param diagnosticMessage - The diagnostic's message text.
+ * @returns `true` if the diagnostic should be suppressed.
+ */
+export function shouldSuppressDiagnostic(specifiers: string[], diagnosticMessage: string): boolean {
+  if (specifiers.length === 0) {
+    return true; // no specifiers → suppress everything
+  }
+  const lowerMessage = diagnosticMessage.toLowerCase();
+  return specifiers.some((spec) => lowerMessage.includes(spec));
+}
+
+/**
+ * Filters an array of diagnostics, removing any whose starting line is
+ * immediately preceded by a `# yaml-lint-disable` comment.
+ *
+ * When the comment includes one or more comma-separated message substrings,
+ * only diagnostics whose message contains at least one of those substrings
+ * (case-insensitive) are suppressed.  Without specifiers, all diagnostics
+ * on the next line are suppressed.
+ *
+ * @param diagnostics - The diagnostics to filter.
+ * @param getStartLine - Extracts the zero-based starting line number from a diagnostic.
+ * @param getMessage - Extracts the message string from a diagnostic.
+ * @param getLineText - Returns the text of a document line by its zero-based index,
+ *   or `undefined` if the line is out of range.
+ * @returns A new array containing only the diagnostics that are not suppressed.
+ */
+export function filterSuppressedDiagnostics<T>(
+  diagnostics: T[],
+  getStartLine: (diag: T) => number,
+  getMessage: (diag: T) => string,
+  getLineText: GetLineText
+): T[] {
+  return diagnostics.filter((diag) => {
+    const line = getStartLine(diag);
+    if (line === 0) {
+      return true; // no preceding line to check
+    }
+    const prevLineText = getLineText(line - 1);
+    if (prevLineText === undefined) {
+      return true; // couldn't read the line — keep the diagnostic
+    }
+    const match = YAML_LINT_DISABLE_PATTERN.exec(prevLineText);
+    if (!match) {
+      return true; // no disable comment — keep the diagnostic
+    }
+    const specifiers = parseDisableSpecifiers(match[1]);
+    return !shouldSuppressDiagnostic(specifiers, getMessage(diag));
+  });
+}

src/extension.ts

@@ -21,6 +21,7 @@ import { getConflictingExtensions, showUninstallConflictsNotification } from './
 import { TelemetryErrorHandler, TelemetryOutputChannel } from './telemetry';
 import { createJSONSchemaStatusBarItem } from './schema-status-bar-item';
 import { initializeRecommendation } from './recommendation';
+import { filterSuppressedDiagnostics } from './diagnostic-filter';
 
 export interface ISchemaAssociations {
   [pattern: string]: string[];
@@ -140,6 +141,27 @@ export function startClient(
     initializationOptions: {
       l10nPath,
     },
+    middleware: {
+      handleDiagnostics(uri, diagnostics, next) {
+        const doc = workspace.textDocuments.find((d) => d.uri.toString() === uri.toString());
+        const getLineText = (line: number): string | undefined => {
+          try {
+            return doc?.lineAt(line).text;
+          } catch {
+            return undefined;
+          }
+        };
+        next(
+          uri,
+          filterSuppressedDiagnostics(
+            diagnostics,
+            (d) => d.range.start.line,
+            (d) => d.message,
+            getLineText
+          )
+        );
+      },
+    },
   };
 
   // Create the language client and start it